1. Field of the Invention
The present invention relates to a three-dimensional micro-electronic device structure and, particular, to such a device in which information is transferred through stacked wafers inter-connected with adjacent wafers with topological one-to-one correspondence.
2. Description of the Prior Art Including Prior Art Statements
Rapid advances in the science and technology of micro-electronics have led to a rapid growth in the power of digital computers, for example, in their ability to calculate and process data. Even so, in recent years the increasing need for processing two-dimensionally organized data has out-striped the power of the electronic digital computer in several important areas of application. These applications mainly involve near real-time machine processing of video, and wideband signals from radar or digitized infrared imagery, and solving multi-dimensional, non-linear parallel differential equations governing such physical systems as meteorology and aero-dynamics. For example, the enormous quantity of information on a single continuous-tone high-resolution photograph challenges the capabilities of even the larger-present-day electronic digital computers. As a result, near real-time analysis of the multi-image input from video or infrared imaging systems exceeds the capabilities of conventional serially organized electronic digital computers.
Elements of present-day electronic digital computers transfer information through leads on a surface of a chip or a wafer to its edge and then through external leads to another wafer. Such interconnections limit the number of channels of information, and result in very large physical size and power consumption with associated heat removal problems, high price, and relatively long interconnections. For example, this type of architecture precludes the use of low power logic, which is too slow to be used in serially structured machines for high data rate applications. Power requirements are relatively high, also because the high frequency, long lines have to be low impedance (50 ohm) matched transmission cables. The resultant system size is large becuase of its requirements for printed boards, connector cables, packages and the like. The price is high because of the high labor content of fabrication of and interconnections within printed circuit boards and packaging of the chips.